Greek Anthology Book XIV: Metrodorus: 141

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Arithmetical Epigram of Metrodorus

Tell me the transits of the fixed stars and planets when my wife gave birth to a child yesterday.
It was day, and till the sun set in the western sea it wanted six times two-sevenths of the time since dawn.


Solution

Let $t$ be the time since dawn that the birth happened.

It is assumed that the day is $12$ hours long.


We have:

\(\ds t\) \(=\) \(\ds 6 \times \dfrac 2 7 \paren {12 - t}\)
\(\ds \leadsto \ \ \) \(\ds 7 t\) \(=\) \(\ds 144 - 12 t\) multiplying through by $7$ to clear the fractions and simplifying
\(\ds \leadsto \ \ \) \(\ds 19 t\) \(=\) \(\ds 144\)
\(\ds \leadsto \ \ \) \(\ds t\) \(=\) \(\ds \frac {144} {19}\)
\(\ds \) \(=\) \(\ds 7 \frac {11} {19}\)


So $7 \frac {11} {19}$ hours had passed since dawn when the baby was born.

That leaves $12 - 7 \frac {11} {19} = 4 \frac 8 {19}$ hours remaining till sunset.

$\blacksquare$


Source of Name

This entry was named for Metrodorus.


Sources